William J. Brennan, Jr., Blystone v. Pennsylvania — Dissenting Opinion
“ Just as a jury must be free to consider and weigh mitigating circumstances as independently relevant to the defendant's moral culpability, see Penry, supra, at 319, 109 S.Ct., at 2947, a jury must also be able to consider and weigh the severity of each aggravating circumstance. The weight of an aggravating circumstance depends on the seriousness of the crime-a significant aspect of the defendant's moral culpability. Thus, a reasoned moral response to the defendant's conduct requires the consideration of the significance of both aggravating and mitigating factors. ”
